Power operated plastering trowels



. y 1958 J. D. DRUMMOND 2,836,056

POWER OPERATED PLASTERING TROWELS Filed Oct. 24, 1955 INVENTOR JOHN O. OH UMMOND ATTORNEY United States Patent Patented May 27, 1958 POWER OPERATED PLASTERING TROWELS John D. Drummond, North Burnaby, British Columbia, Canada Application October 24, 1955, Serial No, 542,421

1 Claim. (Cl. 72-=-136) My invention relates to improvements in power operated plastering trowels.

The objects of the present invention are to provide a power operated trowel having two troweling members capable of troweling inside angle planes of walls and ceilings simultaneously and to prevent any plaster displaced by one member from being moved onto the plane being troweled by the other member.

A further object is to provide means whereby the troweling members are shielded to prevent their peripheral edges from cutting into the plaster in the plane adjacent which it is working.

Referring to the accompanying drawings:

Figure 1 is a side elevational view of the invention as seen when not in use.

Figure 2 is an elevational view showing the face of one of the troweling members.

Figure 3 is a detail perspective view showing the manner in which the blades of a troweling member are adjusted.

In the drawings like characters of reference indicate corresponding parts in each figure.

The numeral indicates generally a portable electric motor having a hand grip 11, a face plate 12 and a motor shaft 14. Secured to the face plate 12 of the motor 10 is a sheet metal frame 16 which includes spaced forwardly projecting brackets 17 between which are carried anti-friction bearings 19, 20 and 21. The bearings 19 journal a vertical shaft 23 having secured to its upper end a worm gear wheel 24 which meshes with a worm 25 secured to the free end of the motor shaft 14. The lower end of the shaft 23 is fitted with a mitre gear 26. The bearings 20 journal a vertical shaft 27 to which is secured at its outer end a troweling member 28, and the bearings 21 journal a horizontal shaft 29 which supports at its outer end a second troweling member 30. The shafts 27 and 29 are hollow and are fitted at their inner ends with mitre gears 31 and 32 respectively, which gears mesh with each other and the gear 32 meshes with the mitre gear 26.

The troweling members each consists of a central disk 33 upon which are mounted preferably by riveting a plurality of spring blades 34 having trailing edges 35 which are adapted to bear upon the face of the plaster to be finished. The trailing edges have their outer ends leading their inner edges so as to wipe any plaster or Water engaged thereby towards the axis of the troweling member. All of the blades are contacted on their outer faces with one or more set screws 37 which serve to adjust the frictional bearing of each blade on a plastered surface. The outer end of each blade 34 is rearwardly turned away from the working surface to form a rim portion 39 which serves to prevent the outer edges of said blades from cutting into the face of an adjacent wall.

It will be obvious that the troweling members 28 and 30 are of the same diameter and that the length of the blades of each will extend radially to the plane of the blades of the other, so that an internal angle of two adjoining walls having been plastered can have a width equal to the diameter of each troweling member and extending on both sides of the intersection of said walls troweled simultaneously as the tool is moved lengthwise of the intersecting line.

A valve 40 is fitted in any convenient position on the frame 16 and a water supply hose 41 is carried to said valve, two small hoses 43 extend from said valve through each of the shafts 27 and 29 and connect with nozzles 45 in the centre of each disk 33, one only shown. A handle 47 is mounted on any convenient part of the frame 16', so that the device may be conveniently lifted and manipulated by both hands.

Obviously when the machine is at rest it will stand, as shown in Figure l, with the troweling member resting upon a horizontal surface. When in use it will be raised and manipulated to present each of the troweling members 28 and 30 to a plastered area consisting of two intersecting walls or the intersection of a wall and ceiling. The device will be reciprocatcd lengthwise of the corner, troweling both areas to the width of each of the troweling members. Water as desired is forced onto the plaster face through the nozzles 45 and is worked into the surface as it is hardened and smoothed. The upturned rim portion 39 and the immediate blade area from which they spring trowel the corner to a smooth square angle and prevent scoring of any wall which so frequently occurs in the troweling of a plastered inside angle or corner. Since the tips of the blades 34 of the two troweling members are staggered, one rim portion 39 is almost constantly in operative engagement with a wall surface, thus insuring that the device shall constantly move in a perfectly straight line as it is moved along the corner to be troweled.

What I claim as my invention is:

Power operated trowel comprising a prime mover having a pair of driven shafts disposed at right angles to each other, a rotatable troweling member on each shaft, said members each consisting of a disk having radial work surface contacting blades, said members being mounted with their work surfaces at an angle of substantially ninety degrees to each other to trowel adjoining wall areas forming an inside angle, the blades of one member being staggered with respect to those of the other member, each blade having an upturned rim portion at its outer end, the rim portions of the blades of one member being adapted to alternate with the blades of the other member to trowel the intersecting angle of the two adjoining wall areas.

References Cited in the file of this patent UNITED STATES PATENTS 1,118,576 Perkins Nov. 24, 1914 1,523,049 Campbell Ian. 13, 1925 1,645,317 Carroll Oct. 11, 1927 1,698,970 Shaft Jan. 15, 1929 1,828,576 Palatini Oct. 20, 1931 2,101,895 Boulton Dec. 14, 1937 2,553,688 Thompson May 22, 1951 2,556,983 Root June 12, 1951 

